Post-hole digger.



PATENTED JULY 31, 1906.

C. BUTGHER.

POST HOLE BIGGER.

VMM/55555 Tm am M CHARLES BUTCHER, OF CAMBRIDGE, MASSACHUSETTS.

POST-HOLE DIGGER.

Specification of Letters Patent.

Patented J' uly 31, 1906.

Application filed February 23, 1906. Serial No. 302.411.

To @ZZ whom iv may oon/cern:

Be it known that I, CHARLES BUTCHER, a citizen of the United States,residing at Cambridge, in the county of Middlesex and State ofMassachusetts, have invented new and -useful Improvements in Post-HoleDiggers,

granted to me March 15, 1904, No. 754,421,

and September 12, 1905, No. 799,445. In th1s instrument the scoop orblade is pivoted to the lower end of the handle and adapted to be swungfrom substantially a vertical downward digging position to a horizontal'earth-removing position while still inserted in the earth, whereby theearth may be removed from a vertical hole of small diameter.

The objects of the improvement are to improve the mechanism and increasethe facility and convenience of operation and to render the instrumentautomatic in certain respects. These objects are attained by the meansillustrated in vthe accompanying drawings, in which- Figure 1 is a frontelevation of one form of the device, showing it ready for digging. Fig.2 is a central longitudinal section on the line 2 2 of Fig. l. Fig. 3 isa side elevation showing the blade in position for removal of earthvertically. Fig. 4 is a partial rear view of the upper part of thehandle. Fig. 5 is a cross-section on the line 5 5 of Fig. 3. Fig. 6 i anenlarged longitudinal section of a detai Similar letters refer tosimilar parts wherever they occur in the drawings.

,Referring to the drawings, A represents the handle, to the lower end ofwhich is pivoted a blade B of any desired form or size. A bar C lieslongitudinally on the handle and is movable longitudinally thereonwithin a casing D. It is attached at its lower end C to a rod E, whichis connected to the sides of the blade in any suitable manner. In theform illustrated this rod starts with a hook E on one side of the blade,passes to its connection C with the bar C, and then passes down to theother side of the blade, where there is a similar hook E. Obviously whenthe blade is turned downward upon its pivot this rod and its connectedbar C will be drawn downward upon the handle. A post A is set in thehandle to limit the downward motion of the bar. This post is T-shaped,the stock of the post being placed centrally in the path of the movingbar C and the crossarms rojecting sidewise across the rod E, thusblnding it loosely to the handle and serving as a guide and guard tohold the rod E and lower end of bar C in their pro er positions close tothe handle A. As t e strain upon these parts when earth is being liftedfrom the hole tends to draw them outward away from the handle, thisT-guide serves an important function in strengthening this part of themechanism and relieves the casing D of the strain, thus enabling thelatter tobe made of lighter material, which is more easily worked orformed into shape andmakes less weight to handle when using theinstrument.

The bar C is provided with a rack, and there is a pawl F set in thehandle, the two being so shaped as to permit upward movement' of thebar, but not downward movement. The pawl is operated by a lever H, whichengages a neck formed in the outer end of the pawl, and by this leverthe pawl is moved into engagement or out of en agement. In my previousatent this paw was shown as engaged direct y by a spring, which wasformed with a fork embracing said neck. One feature of the presentinvention is an improvement on that in which the spring G is notattached directly to the pawl, but acts upon the lever and produces itseffect upon the awl only through the medium of the lever.

y this construction it is not necessary to cut any metal from the sring, and thus the spring may retain its ful strength and the danger ofbreakage in cutting the spring is obviated. The danger of breakageduring S is arranged on the handle adapted to engage a shoulder onrack-b ar C, which shoulder may conveniently be the upper end of thebar, as

shown in Fig. 2, to prevent upward motion 100 the lever Q to press thepawl normally to- 105 ward its position of engagement through the mediumof said lever. This pawl is so located with respect to the end of therack-bar that it will engage the same automatically whenever the latteris dropped to its lowest 1ro operation is also minimized. Another pawlposition (shown in Fig. 2) and only then, its face being beveled, sothat it 'rides harmlessly over the rack when the bar is inraisedposition. Its locked position corresponds to the downward position ofthe blade into which the same is adjusted when it is to be used fordigging. Upon dropping the blade to this position the awl automaticallylocks it there and the wor man uses the device as a stiff-bladed shoveluntil he is ready to change the same to a scoop, when he presses uponthe releasing-lever Q and begins to rock the handle backward andforward. This causes the blade to gradually work into the horizontalposition shown in Fig. 3. The racl bar meanwhile works gradually upwardduring the oscillating movement from the position shown in Figs. l and 2to that of Fig. 3. During this operation the pawl S produces no eiect,and the pawl F is in operation, engaging the rack-bar at each successivenotch as the same works upward. Then the operator lifts the instrumentfrom the excavation, bearing loose earth on the blade, which has thusbecome horizontal. After discharging the earthfrom the blade pressureupon the lever H releases the rack-bar, the blade falls and becomesautomatically locked in its downward position. By reason of theautomatic' .feature no reliance need be placed on the memory of theoperator, and considerable time may be saved by making certain that theblade is in digging position each time it is introduced into the hole,thus preventing itv from changing its angle while being manipulated inthe earth until the operator attendsto releasing it.

I claim- 1. In combination with a handle and a blade pivotally connectedthereto, a rod con- 4o nected to the blade and guided longitud nally onthe handle 5 and a T-post set in the handle constituting a stop and aguide for the rod.

2. In combination with a handle and a blade pivotally connected thereto,a movable bar connected to the blade and guided on the handle; means tolatch the bar against motion in one direction 5 a lever controlling saidlatch, and a spring arranged to operate the latch through the medium ofthe lever.

3.- In combination with a handle and a blade pivotally connectedthereto, a bar connected to the blade and guided on said handle; and anautomatic latch on thehandle, arranged to engage the bar when in itsdownward position and thus lock the blade rigid.

4. In a posthole digger, the combination,

with a handle and a blade pivoted at one end of the handle, of a barconnected with the blade and movable longitudinally 4on the handle meansautomatically engaging the bar when in its lowest position to prevent uward motion thereof means automatical y engaging the bar when not in itslowest position to prevent downward motion thereof; and means formanually releasing each of said automatic engaging means.

In testimony whereof I a'HiX my signature in presence of two subscribingwitnesses. Y

CHARLES BUTCI-IER.

Witnesses i EVERETT E. KENT, OLIVER P. SoHooNMAKER.

